Field of the Invention
The present invention relates to a radiation imaging apparatus and a radiation imaging system.
Description of the Related Art
There is known a radiation imaging apparatus for causing a scintillator to convert, into light, radiation which has been emitted from a radiation source and passed through an object and causing a sensor array having a plurality of arrayed sensors to detect the light, thereby obtaining an image. Radiation imaging apparatuses are classified into a type in which a scintillator is arranged between a radiation source and a sensor array and a type in which a sensor array is arranged between a radiation source and a scintillator. The latter type is described in Japanese Patent No. 3333278 and is excellent in high image quality and high detection efficiency of light converted by the scintillator.
Since the scintillator and the sensor array are fragile, it is important how they are supported in a housing. Japanese Patent Laid-Open No. 2014-2114 describes a radiation imaging apparatus including a housing having first and second plate portions arranged to oppose each other, a sensor panel arranged between the first and second plate portions, and a scintillator arranged between the sensor panel and the second plate portion. The sensor panel includes a sensor array in which a plurality of sensors for detecting light are arranged in an array. The radiation imaging apparatus includes a supporting portion arranged between the scintillator and the second plate portion so as to support the scintillator and a member arranged between the sensor panel and the first plate portion and made of a material having a buffer function of buffering a shock. The member is configured so that the outer edge of the sensor array is fitted into the outer edge of the member, thereby forming a space around the member.
In the arrangement in which the member having the buffer function is arranged between the first plate portion of the housing and the sensor array, as described in Japanese Patent Laid-Open No. 2014-2114, the member is required to have a sufficient radiation transmittance in addition to a sufficient buffer function for protecting the sensor array. For this reason, the degree of freedom of selecting a material for the member can be limited.